To the present date solar trackers may be provided with a degree of freedom such as two degrees of freedom known in the sector as single or dual axle trackers. The dual axle trackers enable tracking from east to west (azimuth tracking) and elevated tracking, which enables up to 30% more energy to be captured compared with fixed installations.
Dual axle tracking systems currently in the state of the art are provided with photovoltaic panels grouped over large surfaces and are sustained by a single post, which is provided with the means required for providing two degrees of freedom to the surface comprising all the grouped panels, enabling azimuthal orientation and in elevation of the group surface area.
This configuration of the tracker comprising a post with a dual degree of freedom, the upper end of which is provided with a series of photovoltaic panels grouped together and forming a surface, does, however, pose a number of disadvantages.
Generally, for the purpose of maximising the dual axle tracker, the surface to be controlled is usually relatively large, from various dozens of m2 upwards to almost 100 m2. This means that the surface wind resistance is considerable and therefore the structure needs to be enlarged in order to provide it with sufficient resistance, not only to support the wind force, but also the rotation moments resulting from asymmetries in pressure distribution which also requires over-sizing of the actuators in order to control the positioning of the apparatus.
Given that the surface is usually relatively large, in order to orient it in an appropriate manner, the posts are required to be of a certain height, which involves difficulties in erecting each of the trackers, in addition to the fact of their obvious visual impact.
The arrangement of the panels in single post structures hinders the implementation of control algorithms which enable reduction of the impact of the shade projected by nearby structures thus requiring greater separation between trackers.
This distancing between trackers in order to avoid casting shade over each other, implies a less effective use of land in respect of installed power per square metre.
Additionally, in its erection procedure, this type of dual axle tracker mounted on a single post requires a considerable degree of specialisation both in terms of manpower and machinery, and this involves additional costs in terms of materials and time, resulting in considerably higher costs.
Therefore, the objective of the present invention is to overcome the aforementioned disadvantages by developing a dual axle tracker, which on one hand has little wind sensitivity, such that its erection structure has minimum structural resistance requirements, and to facilitate its erection by providing it with a certain degree of tolerance, thus making better use of land as it permits more installed power per square metre.